uof It is a document file format developed in China by Chinese office of software work group (COSWG). It is an open standard for office applications sometimes known as unified office format. It includes presentation, words processing and spreadsheets. Although there are specific applications for each which are widely and commonly used compared to UOF, for text documents(UOT), Presentation(UOP), and spreadsheets(UOS).
dif A .dif extension file is a Data Interchange Format file that is in a text format. The DIF file is used for importing or exporting a standard format file into other compatible formats. This format has been developed by Microsoft and has the ability to enable importing/exporting a single spreadsheet between programs that can open spreadsheets.